Carl j



(ModeL) G. J. A. SJOBERG.

LOCK.

No. 409,119. Patented Aug. 13,1889.

I invenmr: CZrZJAQ Merf 4v UNITED STATES PATENT OFFICE.

CARL J. A. SJOBERG, OF ROOKAXVAY, NE JERSEY.

' LOCK.

SPECIFICATION forming part of Letters Patent No. 409,119, dated August 13, 1889. Application filed May 29, 1888. $erial No. 275,4'29. (Model) cation.

My invention relates to looks; and it consists of certain improvements which are fully set forth in the following specification, and shown in the accompanying drawings, which form a part thereof.

My object is to make a lock which shall be simple in construction and inexpensive to manufacture. Cheap locks are in great demand, particularly for use in sewing-machines, work-boxes, &c., where the object of locking is more to act as a security against accidental loss than to prevent theft. Under such circumstances expensive locks are not desired. A really cheaplock, however, has not hitherto been obtainable, owing to the necessary uses of springs and complicated mechanism, which have greatly increased the cost of making. By my invention, however, the mechanism is very much simplified, and I dispense entirely with loose springs.

One of the main advantages of my lock is its thinness, for, being formed of but three flat. pieces of sheet metal, there is nothing to make it bulky. This has its advantage in that it requires but little cutting away of the wood-work, and may be fitted to drawers and boxes in which the edges are very thin and to which ordinary locks now found on the market are not adapted.

I have shown in the drawings several different forms in which my lock may be constructed; but it is apparent that my invention is capable of other variations than those illustrated, and that the details of construction may be varied in many ways.

Figure 1 is a perspective View of a lock embodying the principles of my invention, having the back plate fixed. Fig. 2 is a similar View of the same, in which the back plate is raised to disclose the interior mechanism of the lock. Fig. 3 is a cross-sectional View of the same throughthe line as :r of Fig. 1. Fig. 4 is a plan view of the same with the back plate removed, showing the position of the parts when the bolt is shot. Figs. 5 and 6 are perspective views of modifications of my lock in which two bolts are used; and Fig. 7 is a plan view of the modification illustrated in Fig. 6 with the back plate and key-plate removed, showing the bolts shot.

A is the main or body plate, having one edge turned up into a flange B, in the usual manner, for attachment to the drawer or object upon which it is to be used. A portion of the rim may be turned up on the other side, as is shown in the drawings at b, to hold the parts better inplace.

O is the spring back plate, provided with projections c, which fit through slots a in the main plate for the purpose of holding the parts together.

D is the key-plate, of asubstantially circular shape, but preferably provided with a lug d, the object of which is to prevent the keyplate from turning too far when the bolt is unshot or drawn back. Extending from the key-plate is the bolt E, which is curved in shape, as shown in Figs. 1 to 5; but a straight bolt may be used, as shown in the modifications in Figs. 6 and 7. In my preferred construction this bolt E is connected to the keyplate D by a short neck F, and the inner or rear end of the bolt is slightly extended, thus forming the indentations or notches f and f. The back plate C is provided with a small pin or projection G, formed, if desired, by pressing up the plate, and which normally (when the bolt is unshot) extends into the indenta tion or curve f, projecting just sufficiently beyond the neck F to keep the key-plate from turning. \Vhen, however, by the use of a key the key-plate is turned, the neck F is forced under the projection G, which snaps again into the indentation or opening f of the other side and holds the bolt shot.

The back plate is formed of sheet-steel very thin and bent into the desired shape, and when in place provides a spring action of the proj eci ion Gupon the neck F, making it snap upon either side. All of the parts are of stamped sheet metal, and consequently the lock, being of only three thicknesses of sheet metal, is very thin and is readily fitted to a drawer or box with but a minimum removal of the wood for its reception. Most locks are thick and bulky and require the cutting away of much wood; but this is obviated in this improved lock.

ICO

It is apparent that in place of cutting the key-plate into the notches f and f to form the neck F, small holes or recesses might be made at the same points in the key-plate to receive the projection G, as indicated in dotted lines in Fig. By extending the inner or rear end of the bolt E the lug (Z on the keyplate may be dispensed with, as the end of the bolt would accomplish the same result.

II is the key-hole in the main or body plate,

and is round. I is a slot in the key-plate to receive the key. "While this slotis shown in the drawings in a simple square or rectangular form, it is apparent that it maybe modifiedin many ways to suit different styles of keys.

In Fig. 5 is shown a 'key-plate provided with two bolts. In this construction the plate C will preferably be provided with two projeeiions G. It will be observed that the keyplate and the bolt which it carries are guided on two opposite sides by the flanges or rims of the back plate 0, and on the other two opposite sides by the flanges or rims of the main plate A.

In the modification shown in Figs. 6 and 7 two straight bolts are used. This construction, as well as that of Fig. 5, is adapted to use where it is desired to lock two drawers, doors, or lids to an intermediate fixed piece.

The bolts J in this modification have internal curved cam -faces 7', and are placed in relatively-opposite positions to each other, forming by their cam-faces a central opening, as shown in Fig. 6. Acircularkey-plate D is used, and is provided with two pins or projeetionsK on its under surface, located opposite each other and adapted to engage in the cam-faces of the bolts. This key-plate is also provided on its upper surface with four recesses or indentations L opposite each other, and substantially ninety degrees from each other. \Vhen the key-plate D is turned, the pins K, fitting in the cam-faeesj of the bolts, shoot them forward, when the recesses L engage the projections G on the back plate 0 and the bolts are locked shot. The bolts J in this construction are guided by their adjacent sides and the lateral edges of the back plate. These bolts are provided with a shoulder to prevent them being shot too far.

I do not limit myself to the details of construction shown, as it is manifest that many other modifications of my lock may be made by slight alterations of construction without departing from the principles of my invention.

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In a lock, the combination of a key-plate provided with a bolt,a body-plate for attachment of the lock, and a flat spring back plate having a projection adapted to press upon the key-plate and snap upon either edge of it to hold it in its extreme positions.

2. The combination of a body-plate, a flat keyplate having two curved bolts pointing in opposite directions, and a Hat spring back plate adapted to press upon said key-plate and hold it in position to the body-plate, and provided with a projection adapted to press against said key-plate and retain it in position when thebolts are shot.

3. In a lock, the combination of a body and a back plate, a flat key-plate "guided by said main and back plate, provided with recesses or edges, a bolt operated directly by said key-plate, and means, substantially as deseribed, to lock said key-plate and hold the bolt in its shot or nnshot positions, consisting of projections upon said back plate adapted to engage in the recesses or over the edges of said key-plate.

4. In a lock, the combination of a key-plate provided with a belt, a body-plate for attachment of the lock, a flat spring back plate, and a projection upon one of said parts adapted to press upon the adjacent part and hold the key-plate in its extreme positions.

In testimony of which invention I hereunto set my hand.

CARL J. A. SJOBERG. Witnesses:

W. S. LINcoLN, E. W. BEACH. 

